Manhole guardrail



y 1969 T. A. PELSUE 3,444,793

MANHOLE GUARDRAIL Filed May 4, 1967 'INVENTOR.

THURMAN A. PELSUE FIG. 2.

May 20, 1969 Filed May 4, 1967 T. A. PELSUE 3,444,793

MANHOLE GUARDRAIL Sheet Of 2 h 8 2 5 q 2 8 E L fi l 1 L QLQ,

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8 THURMAN A. PELSUE United States Patent 3,444,793 MANHOLE GUARDRAILThurman A. Pelsue, 3706 S. Hibiscus Way, Denver, Colo. 80237 Filed May4, 1967, Ser. No. 636,040 Int. Cl. E02d 29/14 U.S. Cl. 9438 ClaimsABSTRACT OF THE DISCLOSURE This invention consists of an upstandingfoldable tubular guardrail made in three sections, the end sections ofwhich are provided with arcuate brackets adapted to engage the outsidecylindrical surface of a manhole shield of the type shown in U.S. PatentNo. 3,294,000 while being held in contact therewith by means of adetachable elastic member stretched between said end sections.

The inventor of the instant invention is also the inventor of theabove-identified patented manhole shield which fits down into and formsa watertight seal with the ring bordering a manhole. A considerableportion of the shield projects upwardly above ground level and servesthe valuable function of providing a standpipe capable of preventingground water produced by rain, melting snow, irrigation and the likefrom entering the manhole to the considerable discomfort of the workmenengaged therein, to say nothing of the possible damage it might do tothe subsurface installations. Thus, manhole shields made in accordancewith the above patent, along with certain other designs that serve thesame general purpose, are becoming more and more widely used by thepublic utilities service people.

While, to some extent, the above-described manhole shields serve thesecondary function of guarding the entrance to the manhole so thatpedestrians and vehicles do not accidently enter same when uncovered,additional protection in the form of a waist-high guardrail is generallyconsidered a necessity. Such guardrails are in common use and have beenavailable for many years in one form or another. In all cases, however,the prior art guardrails for manholes comprise nothing more thanfree-standing fences formed of pipe or some other tubular material andnone of them, to applicants knowledge, connect in any way to the ringsurrounding the manhole or any other accessory used therewith. For thisreason, the guardrail can easily be moved aside by a person walkingagainst it and, as such, the unit fails to provide the measure ofprotection for which it was designed.

The problem of providing a guardrail with the requisite stability toremain in place in a free-standing position also requires that it beconstructed of relatively thickwalled heavy tubing. The weight of theunit thus becomes excessive and it becomes difficult to load and unloadfrom a service truck as well as set up in the street around an openmanhole, especially when it is considered that the user must eitherstand outside thereof or straddle the manhole opening when doing so.

Uneven terrain in the area immediately surrounding the manhole alsomakes it diflicult to use a free-standing guardrail. Even in citystreets and alleys, the built-in crowns and troughs render such unitshighly unstable.

The instant manhole guardrail, on the other hand, eliminates theaforementioned difliculties by connecting the rail to thesolidly-anchored manhole shield. The manhole shield fits down inside themetal ring bordering the manhole and is securely, although removably,fastened thereto by an inflatable gasket. The metal standpipeformingring that projects several inches above ground level provides an idealelement to be used for anchoring the guardrail.

The guardrail is equipped with arcuate brackets shaped to engage theoutside cylindrical surface of the standpipe portion of the shield andthus leave the entry to the manhole completely unobstructed. The tensionelement stretched across the free edges of the guardrail end sections atabout the level of the entry to the standpipe securely holds these unitsin assembled relation so that they are not disturbed by wind, accidentalbumping and the like. A chain is also preferably fastened across theentry way at a higher level to keep pedestrians from falling into theopen manhole. With the guardrail anchored in this fashion, it can befabricated from lightweight tubular stock which is much easier tohandle, yet serves the purpose just as well.

It is, therefore, the principal object of the present invention toprovide a novel and improved manhole guard rail.

A second objective of the invention herein disclosed and claimed is theprovision of a manhole guardrail specifically designed for use incombination with an upstanding manhole shield of the type removablyfastened to the metal ring bordering a manhole.

Another object is to provide a manhole guardrail that is lightweight yetunaffected by wind and accidental bumping when properly anchored to theshield.

Still another objective is the provision of a manhole guardrail that isformed in three foldable sections for easy handling and storage.

An additional object is to provide a unit of the type aforementionedthat is held in clamped position encircling the shield by means of atension member removably fastened between the free edges of the endsections.

Further objects are to provide a manhole shield that is rugged, stable,compact, easy to use, inexpensive, adaptable for use with various typesof manhole shields and decorative in appearance.

Other objects will be in part apparent and in part pointed outspecifically hereinafter in connection with the description of thedrawings that follows, and in which:

FIGURE 1 is a top plan view showing the manhole guardrail of the presentinvention fastened in place on the standpipe portion of a manholeshield, the latter having been indicated in dotted lines;

FIGURE 2 is a front elevation of the guardrail alone;

FIGURE 3 is an enlarged fragmentary view, portions of which have beenbroken away and shown in section, revealing the joints that enable theend sections to be folded in upon the center section;

FIGURE 4 is a front elevation similar to FIGURE 2 except that both endsections are shown swung outwardly into alignment with the centersection;

FIGURE 5 is a horizontal section taken along line 5-5 of FIGURE 4showing the shape of the shield-engaging brackets; and,

FIGURE 6 is a fragmentary front elevation showing the manner in whichthe brackets engage and grip the cylindrical outer surface of themanhole shield.

Referring now to the drawings for a detailed description of the presentinvention, the manhole guardrail which has been broadly designated byreference numeral 10 will be seen to include a middle or center section12 hingedly connected on both sides to end sections 14 and 16 that aremirror-images of one another. Each of the end sections 14 and 16 share acommon upright 18 and 20 with the center section, the latter elementscomprising vertical tubular elements arranged in transversely-spacedparallel relation to one another. Uprights 18 and 20 are each providedwith a lower collar 22, middle collar 24 and upper collar 26, all ofwhich are fastened more or less permanently as by welding althoughrivets or even set screws could be used. Resting atop collars 24 and 26are short tubular sleeves 28 and 30, respectively, that turn freely ontubular uprights 18 and 20. Tubular sleeves 32, on the other hand, restagainst the underside of collars 22 and are similarly rotatable uponuprights 18 and 20. Fixed collars 34 welded or otherwise fastened touprights 18 and 20 abut the underside of rotatable sleeves 32 and holdthem against fixed collars 22. In like fashion, fixed collars 36fastened to the uprights 18 and 20 holds sleeves 28 against collars 24as do fixed collars 38 with respect to sleeves 30 and collars 26.

The center section 12 of the guardrail is completed by upper horizontalrailing 40 connected between rotatable sleeves 30 middle horizontalrailing 42 connected between the middle set of rotatable sleeves 28, andlower horizontal railing 44 interconnecting sleeves 32. The foldableleft and right end sections or wings 14 and 16 each include verticaltubular uprights 46 and 48 arranged in spaced parallel relation to oneanother and to uprights 18 and 20. Upper horizontal railings 50 areconnected at their adjacent ends to fixed collars 38 and extendoutwardly therefrom to a point of attachment with uprights 46 and 48near the top thereof. In like fashion, middle railings 52 are connectedbetween fixed collars 36 and uprights 46 and 48 at a point intermediatethe ends of the latter. These wings 14 and 16, however, include no lowerrailing corresponding to railing 44 of the center section but, instead,substitute curved metal brackets 54 therefor that are connected betweenfixed collars 34 and uprights 46 and 48. These brackets, as will beexplained in detail presently, engage the cylindrical outer surface 56of manhole shield 58 to hold the guardrail in place as shown mostclearly in FIGURE 6.

With specific reference to FIGURES 1 and 4, it will be seen that thewings 14 and 16 are very nearly the same width overall as the centersection 12 so that when arranged as shown in FIGURE 1, the wings areparallel to one another and perpendicular to the center section therebyproviding a guardrail along three sides of the open manhole 60. In orderto fold the guardrail for storage, left wing 14 is swungcounterclockwise as viewed in FIG- URE 3 through an arc of about 90 upagainst center section 12 while the right wing 16 is swung in the samedirection through a 270 arc until it rests against the back of thecenter section.

It would, perhaps, be well to mention at this point that the particulararrangement of fixed collars and rotatable sleeves on uprights 18 and 20can be varied considerably, both with respect to position and withregard to the railing member to which they are fastened, and stillpreserve the desired foldability of the unit. The particular arrangementshown is, therefore, merely illustrative of one way in which the endsections or wings can be hingedly attached to the center section, therebeing several others that would immediately occur to those of ordinaryskill in the art. There is, however, a reason for locating brackets 54underneath railing 44 instead of above same as is the case with railing52 relative to railing 42 and railings 50 with respect to railing 40. Aspreviously mentioned, the instant guardrail was specifically designedfor use with the patented manhole shield 58 which, as shown in FIG- URE6, has a pair of vertically-spaced continuous annular flanges 62 and 64bordering the upper end thereof which leave only a few inches ofcylindrical surface 56 exposed above ground level that are available forengagement by the brackets 54. Also, when so located, bottom railing 44of the center section 12 fits neatly into the space 66 left betweenflanges 62 and 64. At first glance, it would appear that brackets 54would, just as easily, fit into the space 66 between the flanges 62 and64 while railing 44 passed therebeneath; however, this is not the casebecause in some oversize manholes, shield 58 is turned upside downleaving gasket 68 exposed which is of lesser diameter and, for thisreason, would not mate properly with brackets 54. Cylindrical surface56, on the other hand, remains exposed in both positions of the shieldand enables bracket 4 54 to be shaped to conform exactly thereto.Obviously, when the instant guardrail is used with a non-reversiblemanhole shield, the above-described refinements may be unnecessary.

Next, with reference to FIGURES 1 and 5, it will be seen that the twoshield-engaging brackets 54 are identical and each is fabricated from alength of strap iron. The significant portion of brackets 54 is thearcuate section 70 thereof that is curved on the same radius as theouter cylindrical surface 56 of the shield. The width of the guardrailsections 12, 14 and 1 6 is selected to lie wholly outside shield 58 asshown in FIGURE 1 so that the arcuate sections 70 of the bracketsapproach the wings 14 and 16 tangentially at about their midpoints.These arcuate sections 70 are approximately 90 in angular extent in theparticular form shown which means that the straight portions 72 thatinterconnect the extremities of the arcuate portion with the respectiveuprights 38, 46 and 48 extend more or less radially with respect to thecenter of the shield when in the operative position shown in FIGURE 1.

Finally, with reference to FIGURES 1 and 2, it will be noted thatuprights 46 and 48 are each provided With transversely-aligned weldedeyes 74 near the lower ends thereof and a tension member 76 withsnaphooks 78 on the ends thereof is detachably stretched therebetween tohold the brackets 54 on the wings 14 and 16 in tight engagement withcylindrical surface 56 of shield 58. In the particular form shown inFIGURE 2, tension member 76 comprises an elastic band; however, othertypes of tension members such as springs and the like will also sufficefor this purpose. Another set of eyes 80 are welded to the uprights 46and 48 near the upper ends thereof to receive the hooks 82 on theopposite ends of chain gate 84. The latter element, of course, guardsthe open entryway to the manhole and is removed when personnel andequipment are lowered therein.

The sole remaining feature left to be described is that of eyes 86 thatare welded atop rails 50 in position to secure a canvas tent flap (notshown). Such a flap can either be laid over the top of the guardrail toprevent rain from entering the manhole or draped down the sides as awind break.

Having thus described the several useful and novel features of themanhole guardrail of the present invention, it will be apparent that themany worthwhile objectives for which it was designed have been achieved.Although but a single specific embodiment of the invention has beenillustrated in the accompanying drawings, I realize that certain changesand modifications therein may well occur to those skilled in the artwithin the broad teaching hereof; hence, it is my intention that thescope of protection afforded hereby shall be limited only insofar assaid limitations are specifically set forth in the appended claims.

What is claimed is:

1. A manhole guardrail for use with a hollow cylindrical manhole shieldof the type that is removably fastened inside the ring bordering amanhole and includes a portion projecting upwardly therefrom whichcomprises: two or more upstanding barrier sections hingedlyinterconnected to form a fence of a length adapted to partially enclosethe manhole shield, said fence having its free ends spaced apart todefine an entryway; brackets mounted adjacent the lower edge of thefence in position to engage the shield at opposed points to the rightand left of the entryway; and, a tension member adapted to be stretchedacross the entryway and hold the brackets against the shield.

2. The manhole guardrail as set forth in claim 1 in which: the fencecomprises three barrier sections, the two endmost barrier sections eachbeing hingedly connected to a center barrier section on opposite sidesthereof for hinged movement about horizontally-spaced substantiallyparallel vertically-disposed hinge axes.

3. The manhole guardrail as set forth in claim 2 in which: the bracketscomprise arcuate members projecting inwardly from the lower extremitiesof each of the endmost barrier sections, said arcuate members beingshaped to conform with the outside cylindrical surface of the shield.

4. The manhole guardrail as set forth in claim 2 in which: each of thebarrier sections is substantially planar and rectangular in shape so asto fold into essentially face-to-face parallel relation to one anotherwhen not in use.

5. The manhole guardrail as set forth in claim 2 in which: the tensionmember comprises an elongate elastic band having connectors on oppositeextremities thereof adapted for releasable attachment to the free sideedges of the endmost barrier sections.

6. The manhole guardrail as set forth in claim 2 in which: means formingan openable gate is connected between the free side edges of the endmostbarrier sections spaced above the tension member, said gate-formingmeans functioning as a removable barrier guarding the open entryway.

7. The manhole shield as set forth in claim 2 in which: the threebarrier sections are each substantially planar, rectangular in shape andessentially the same width, the endmost sections being foldable intoface-to-face relation against the center section on opposite facesthereof.

8. The manhole shield as set forth in claim 2 in which: each of theendmost barrier sections include a pair of horizontally-spaced verticaluprights interconnected by transverse rail members, and in which thecenter barrier section comprises horizontally-aligned pairs of sleevesmounted for rotation on the adjacent uprights of the endmost barriersections and transversely-extending rail elements interconnecting eachpair of sleeves.

9. The manhole guardrail as set forth in claim 2 in which: the barriersections are sized and adapted to form three sides of a circumscribedsquare with the shield of the center thereof.

10. The manhole shield as set forth in claim 6 in which: thegate-forming means comprises a chain hung between the free side edges ofthe endmost barrier sections across the entryway.

References Cited UNITED STATES PATENTS 806,160 1 2/1905 Metz. 1,741,32312/1929 Lufkin .a 9438 1,882,150 10/1932 Kent 94-38 JACOB L. NACKENOFF,Primary Examiner.

